49ers head coach Jim Harbaugh has a lot on his plate this season, mixing in newcomers and a new stadium in Santa Clara.

49ers head coach Jim Harbaugh has a lot on his plate this season,...

For the hard-core, this week is like Christmas, Valentine's Day and the arrival of the Tooth Fairy all wrapped into one. Their love affair resumes with the helmeted ones, who will hone their craft on hot, dry fields, in pads and in shorts, in ice baths and meeting rooms, while fanatics scour social media for reports of ankle twinges, dropped passes and sled technique.

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